Official PHP Announcement
Upcoming Critical PHP Security Release
The PHP security team would like to give advance notice of an upcoming security release.
It is scheduled for Wednesday, 21 October 2026 at 14:00 UTC.
It addresses two critical vulnerabilities, both rated CVSS v4.0 9.2.
All PHP users are encouraged to prepare now so they can upgrade as soon as the release is available.
We reserve the right to release earlier should details of either vulnerability become public, or should evidence of active exploitation appear in the wild.
Full details, affected versions, and the fixed versions will be published with the release.
Thank you for helping us keep PHP secure.
Based on rumors it appears to be unauthenticated remote-code-execution targeting a broad section of PHP-based web applications. There also appears to be a video circulating of a proof-of-concept, demonstrating attacks on MediaWiki, WordPress, Drupal, and about a dozen other PHP-based platforms.
Recently, an independent proof of concept has been claimed, but a PHP developer is saying the suggested workaround is insufficient.